Tool-rotating mechanism.



G. H. GILMAN. TOOL ROTATING MEGHANISM. APPLICATION FILED MAY 27, 1907.

Patented July 30, 1912.

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UNITED STATES PATENT OFFICE.

GEORGE E. GILMAN, 0F CLAREMON'I, NEW HAMPSHIRE, ASSIGNOR TO SULLIVAN MACHINERY COMPANY, OF CLAREMONT, NEW HAMPSHIRE, A CORPORATION OF MAINE.

TOOIi-ROTATING MECHANISM.

Iatented July so, 1912.

Application filed May 27, 1907. Serial No. 375,826.

My invention relates to mechanism for effecting an automatic rotation of'a tool, the

same being especially, although not exclu-fl sively, intended for the automatic rotation of a drill or other tool used in connection with devices "of the piston hammer type, such as pneumatic hammer drills.

The object of my invention is to'provide an automatic rotating 'mechanism of few parts and simple construction, thereby to I withstand most effectively a severe service,

such as that to which the pneumatic hammer is subjected, and at the same time effective in giving the desired rotation of the tool with .certainty and without attention-on the part of the. operator.

My 'nvention will be best understood by reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more particularly pointed out in the appendedclaims.

In the drawings :Figure 1 shows the external appearance of a well known type of hammer-, drill to which a rotating device constructed in accordance with one form of my invention has been applied; Fig. 2 shows a central longitudinal section taken through the principal working parts of the rotating device, and showing their relation to the piston hammer and the tool, and Fig. 3 is a transverse section through the rotating mechanism, taken on the line 3-3 of Fig. 2.

Referring to the drawings and to the embodiment of my invention therein shown, the same is illustrated as applied to a hammer drill of an ordinary and usual type comprising the main cylinder portion 1, valve block 2 attached thereto, the handle portion 3 secured to the valve block, and a chuck or tool holding member 4 mounted at the opposite end of the device. Within the cylinder there is provided a reciprocatory piston 5, which, under the influence of compressed air or other pressure fluid admittedalternately to V opposite ends thereof, and under the control of a suitably constructed valve (not shown),

'is caused to reciprocate within the cylinder,

the hammer or striking end 6 of the piston being caused to strike the opposing inner end 7 of the drill 8 a forcible blow at each forward'stroke of the piston.

, The construction of the valve and the passages controlled thereby, of which passage 9 only (Fig. 2) is shown may be of any usual type, well understood to those skilled in the art, the particular construction of the hammer, so far as shown; and the type of' the tool itself, having no significance in connection with my invention, and being shown merely .for the illustration thereof.

In the illustrated form of my invention, in order automatically to rotate the drill 8 so that, during the continued action of the hammer, and through the action of the hammer itself, the drill will be'caused to exe cute a step by step rotative movement, the squared head or end of ,the drill is nonrotatively secured within the end of the bushing 10, which squared head fits acorrespon ingly squared opening in the inner end of the bushing. The latter,-in turn, is

fixedly held by means of a driving or pressed fit within the rotatable chuck 4, the latter being engaged by the piston during its reciprocatory movement to rotate the tool.

Atits opposite or inner end the chuck 4 is I provided with an enlarged or shouldered portion 11 by which it is retained against longitudinal movement in a correspondingly shaped recess in the encircling sleeve-shaped casing 12, wherein the chuck is 'rotatably mounted without, however, being permitted longitudinal movement.

For the assemblage of the parts the forward end of the cylinder 1 is enlarged to provide a-recess or chamber for the reception of the clutch mechanism, the cylinder being provided exteriorly with the inclined walls 13, between the enlarged and reduced portions thereof. The casing 12 has an enlarged open end within which the enlarged cylinder is entered, the casing being also interiorly threaded for threaded en gagement with the binding nut 14. With the parts assembled and the enlarged cylinder end within the enlarged sleeve end, the binding nut 14 is slipped over the reduced.

permits the wedging of the parts together,

so that they cannot accidentally loosen, although, when desired, they can be readily separated by loosening the binding nut 14. Within the chamber at the enlarged forward end of the cylinder is provided suitable clutching mechanism, whereby, on movement of the piston in one direction, the latter is caused to turn through a partial rotation, while, on its return in the opposite direction, it is free to travel without such rotative movement. In order that this partial rotative movement of the piston may act also to rotate the tool, the reduced cylindrical hammer portion of the piston, where it travels through the inner or rear end of the chuck 4, is provided with one or more (herein two) grooves or key-ways 15, which, inthe illustrated construction are straight, that is to say, they extend parallel with the axis of the piston. In sliding engagement with these grooves there are also provided,

respectively, fixed members upon the chuck,

such as the keys 16, so that, while thereciprocatory movementof the piston relatively to the drill is not impeded, it's'rotative movement enforces also a like" rotative movement of the chuck and the drill The several parts thus rotatively joined e. the piston, chuck, bushing and drill, are caused to continue their step by step rotative movement .during the operation of the drill through-means of the clutch mechanism referred to. -While any. suitable clutching mechanism may be employed, to enforce the repeated turning of the. piston when traveling in. one direction while allowing it to return in a straight path, I have herein shown anefi'ective and simple arrangement of parts which accomplishes the desired purpose.

In the illustrated construction the hammer portion of the piston is provided, in addition to the straight grooves 15, also with a pair of helical grooves 17. During its reciprocatory movement it works or slides through an annular member 18, which latter is provided with interior helical keys or teeth 19, which conform to the shape of and have sliding engagement with the helical groove-of the piston, so that as one is held against rotative movement in one direction, the other will, of necessity, be obliged to turn correspondingly in the opposite direction. 7

In order to direct the rotative movement of the pistdn, the annular member 18 is provided on its periphery with a series of grooves forming a succession of teeth 20 which are so shaped that when the toothed member tends to turn in the direction ofthe arrows shown, applied to said member in Fig. 3, it engages one or both of the friction rollers 21 and throws it or them over against the inclined walls 22 of the encircling clutch ring, this action locking it against further rotative movement in that direction.

During the action of the tool, the drill, pressed as it is against the work, ofiers a slight resistance to rotation, and the piston tends to move in a straight line. On its forward movement, therefore, through engagement of its helical grooves with the annular toothed rotating member 18, it tends to rotate the latter in the direction of the arrow shown" in" Fig. 3, and the member 18, therefore, becomes looked as above described, enforcing the rotative movement of: the piston in the opposite direction, or in the direction of the arrows marked upon the section of the piston in Fig. 3, so that before the tool is struck by the piston hammer it has been turned a fraction of a revolution.

On its backward movement the piston, tending as before to move in a straight line, forces the annular rotating member in the opposite direction, and this movement forcing the rollers back out of locking engagement with the inclined walls of the clutch ring and into the open space provided leaves the said member free to slip or turn in the reverse direction, oflering no resistance to the straightaway return 01-6": the piston.

While the clutch ring may be of any suitable construction, I have shown the same split in an axial plane forming the two I halves 23 and24. These substantially fill the longitudinal dimension of the chambered portion of the cylinder. Each half is held fixed within the cylinder against rotative movement by the pins 25 and 26 which are in semi-engagement with each part. 'Each half of the clutch ring is grooved or out awaylaterally at 27 and 28 to provide space for the springs 29 and 30, respectively, the inturned active ends 31 and 32 of which press against the rollers 21 and exert a yielding pressure to keep them in active engagement with the teeth of the annular member 18. The inner face of each clutch ring half is preferably formed so that it just clears the teeth of the annular rotating member18, except where such rings are cut back to form the inclined walls 22, and the enlarged space for the movement of the rollers. The adjacent or abutting end of the remaining frigtion ring half provides in each case an abu' ment to limit the free movement of the adj acent roller.

In operation, it will be clear from the hammer portion of said piston being adaptforegoing description, that the forward movement of the piston effects a looking or "between each blow of the piston, the result being an automatic and effective rotation of the drill so long as the tool is in operation.

It will be obvious that. the apparatus might be so constructed as to cause the turning of the tool on the return of the piston instead of on its advance.

It will be observed that the'described construction provides anextremely compact rotating device, and, presenting, as it does, comparatively few and simple working parts, it is extremely free from likelihood of breakage or disarrangement. Furthermore, this construction provides an assemblage of parts, the principal elements of which 2'. e. the piston, annular rotating member, the chuck and tool, are all united so that they have an intermittent, but continued, rotation in the same direction, it being necessary only to provide clutching or friction parts upon the fixed cylinder adapted alternately to engage and release the rotating member, to effect the turning of the drill. The particular construction described, furthermore, avoids the necessity of placing devices for rotating the piston, such as a rifle bar or the like, within the tool cylinder itself, thereby eliminating a frequent cause for break- While the rotating device described is simple and durable, it is so arranged and 10- cated as to be readily dismantled and inspected for repairs or other purposes.

While I have shown and. described one form of my invention, it is to be understood that the same is not limited to the details of construction or form or relative arrange- 'ment of parts, but that extensive modifications may be made therein without depart ing from the spirit of the invention.

Claims:

1. In a piston-hammer tool, the combination with a cylinder, of a piston hammer having a reduced projecting hammer portion passing through a contracted opening at the forward end of the pressure chamber of the cylinder, and tool-rotating mechanism comprising a tobl-holding ch'uck having a passage therethrough rotatably mounted in said cylinder and at the front of said contracted opening, the reduced projecting ed to move reciprocatively through said 3 of said piston hammer is a o adaptedto move, means connecting said annular memher and said plst-on whereby the locking of the former causes the rotatlve movement of thelatter during reciprocatory movement thereof, and means fixed-in relation to said cylinder for locking said annular rotative member on movement of the piston in one direction while releasing the same for rotative movement of the piston in the opposite direction.

2. In a piston-hammer tool, the combination with a piston hammer and cylinder, of a drill and drill-rotating mechanism comprising a drill-holding chuck having a passage therethrough to which said drill is non-rotatively secured and by which the head of the drill is presented to the hammer blow of the piston, said chuck being rotatably mounted in said cylinder and the end of the piston being adapted to move reciprocatively through the said chuck and a ainst the said drill, means uniting said chuc and said piston to cause rotative moveme'ntg'of the one to .be accompanied bylike rotative of the piston in one direction, while relea'sing the same for rotative movement on movement of the piston in the opposite direction.

3. In a drillr otating mechanism, the com-' binationwith a hammer piston, and a cylinder provided with an enlarged chamber near the forward end through which the piston is obliged to travel, of a drill, a tool holding chuck to which said drill is non-rotatively secured and by which the head of the drill is presented to the hammer blow of the piston, said chuck being rotatively mounted in said cylinder, and the end of the piston extending into the chucking be ing adapted to move reciprocatively through said chuck and against said drill, means joining said chuck and said drill causing rotative movement of the one to be accompanied by like rotative movement of the other, an annular rotating member within;

said chamber, one or more helical grooves upon said piston, helical teeth upon said annular member engaging said groove, or grooves, teeth upon the periphery of said .annular z member, one or more rollers in? -"yielding engagement with said teeth, a

clutch ring Within said chamber fixedly secured to said cylinder and encircling said annular member, said clutch ring acting through said rollers to lock said annular member on movement of the piston in one direction, but to release the same for rotative movement on movement of the piston in the opposite direction. 7

4. In a drill rotating mechanism, the combination with a cylinder of a hammer piston '5 having a reducedprojecting hammer portion 6, a tool rotating mechanism comprising a tool holding chuck 4erotatively mounted and having a cylinder to receive the hammer portion 6,b'ut non-movable longitudinally in saidcylinder, a drill 8 secured in said chuck, the redncedprojecting hammer portion of said-piston being adapted to move reciprocatively through said chuck to strike the inner" end of said drill, means joining said piston and chuck causing rotative movement of the one to be accompanied by like rotative movement of the other, an an tive movement of the latter during reciprocatory movement thereof, and means fixed in relation to said cylinder for locking said annular rotative member on movement of the piston in one direction While releasing the same for rotative movement of the piston in the opposite direction.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

- GEORGE H. GILMAN. Witnesses:

WILLIAM MICHAEL,

H. W.- P. PUTNAM. 

